【Domestic Papers】Effects of Ta concentration on microstructure, optical and optoelectronic properties of Ga₂O₃:Ta films

      Researchers from the Beijing University of Technology have published a dissertation titled "Effects of Ta concentration on microstructure, optical and optoelectronic properties of Ga₂O₃:Ta films " in Vacuum.

Abstract

      Ga₂O₃ material possesses extensive application potential and research value. Doping other elements into intrinsic Ga₂O₃ is one of the common methods to enhance its performance and is also a hot research direction nowadays. In this paper, Ta element was introduced into Ga₂O₃ material, and Ga₂O₃:Ta thin films with different Ta doping concentrations were fabricated using a dual-target RF co-sputtering system. The effects of Ta doping concentration on microstructure, optical, and optoelectronic properties of the films were meticulously investigated, and the optimal Ta doping concentration was determined. XPS results reveal that Ta entered Ga₂O₃ lattice with a +5 oxidation state, and combined with EDS results, it is inferred that Ta successfully partially substitutes Ga. XRD and XPS results indicate that when the sputtering power of Ta₂O₅ is 30 W, corresponding to a Ta doping concentration of 2.39 at.%, the film exhibits enhanced crystallinity. The Ga₂O₃-based MSM detector prepared under this condition demonstrates superior stability and detection sensitivity. Additionally, it also exhibits stable photoresponse to 365 nm light. This work promotes the application of Ga₂O₃ material and provides new insights into improving the stability and performance of ultraviolet photodetectors.

Paper Link：https://doi.org/10.1016/j.vacuum.2024.113142